Jacobs said the surveillance occurred overseas.
Judge William Alsup said on Tuesday that he had only just received the memo, which a former Uber security analyst had sent to one of the company's lawyers.
The hearing instead quickly turned into a forum raising more questions about Uber's ethics and corporate culture.
He also claimed that the team used a secretive messaging system on an anonymous server that would delete texts nearly immediately in order "to ensure we didn't create a paper trail that came back to haunt the company in any potential civil or criminal litigation".
A federal criminal investigation into alleged espionage at Uber has indefinitely delayed a trial over whether the beleaguered ride-hailing service stole self-driving vehicle technology from Waymo, a spinoff from Google.
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Waymo filed suit in February alleging that the ride-hailing company stole crucial self-driving trade secrets. According to Law360, a California judge ruled in Waymo's favor on Tuesday after Waymo accused Uber of hiding evidence that was discovered by federal prosecutors.
His lawyer subsequently wrote a 37-page letter summarizing allegations that Uber used an espionage team to steal its competitors' trade secrets and tried to hide the misconduct by using computers and other devices created to leave no digital trails. The company claimed that Anthony Levandowski, a former Waymo executive, had illegally downloaded 14,000 confidential files before his departure; and he had used that information to start a rival company called Otto, which was later acquired by Uber.
Jacobs said he learned of this activity through discussions at Uber with his manager and other colleagues. The delay of the trial, previously set to kick off December 4, came after Waymo filed a last-minute motion Monday that claimed Uber had "intentionally". Legal trainings within the company also allegedly served to help employees evade investigators.
"We're going to have to put the trial off", Alsup said.
In a statement defending itself, Uber pointed to Jacobs' testimony the he wasn't aware of the company stealing any of Waymo's trade secrets. Anthony Levandowski, an engineer who left Waymo to spearhead Uber's self-driving auto unit, allegedly stole thousands of confidential documents on his way out the door, but Uber has maintained that those documents never reached its corporate servers.